separation vs union

separation and union both are nouns.

Word	Noun	Adjective	Verb	Adverb
separation	Yes	No	No	No
union	Yes	Yes	No	No

separation (noun)	union (noun)
the social act of separating or parting company	the act of making or becoming a single unit
the act of dividing or disconnecting	the act of pairing a male and female for reproductive purposes
(law) the cessation of cohabitation of man and wife (either by mutual agreement or under a court order)	a device on a national flag emblematic of the union of two or more sovereignties (typically in the upper inner corner)
sorting one thing from others	the occurrence of a uniting of separate parts
the distance between things	an organization of employees formed to bargain with the employer
coming apart	a political unit formed from previously independent people or organizations
the termination of employment (by resignation or dismissal)	a set containing all and only the members of two or more given sets
the space where a division or parting occurs	healing process involving the growing together of the edges of a wound or the growing together of broken bones
the state of lacking unity	the state of being joined or united or linked
	the state of being a married couple voluntarily joined for life (or until divorce)

separation (adjective)	union (adjective)
	of trade unions